Pulp washer



Nov. 4; 1947. J. NEUMANN 2,430,135

PULP WASHER Filed Oct. 20, 1943 2 Sheets-Sheet 1 Patented Nov. 4, 1947PULP WASHER John Neumann, Chicago, 111., assignor to Alpha CelluloseCorporation, Van Wert, Ohio, a corporation of Ohio Application October20, 1943, SerialNo. 506,955

This invention relates to pulp washers and its principal object is toprovide a unit wherein paper pulp may be washed, cooked, bleached andrinsed. Another object is the provision of means for introducing washwater into the lower end of the unit together with an overflow openingat the top of the unit whereby the foreign matter contained in the pulpmay be washed out of it and discharged through the overflow opening.Another object is the provision of separately controlled dischargeoutlets for liquid contained in the unit whereby certain liquids may bedrained oil into suitable receptacles for subsequent use and otherliquids may be drained off and conducted away to the sewer or otherplace of disposal. Another object is the provision of a screen protectedperforated false bottom for supporting the pulp and through whichliquids may drain out of the pulp for future disposal. Another object isthe provision of motor operated agitating means for agitating the pulpwhile being washed in the unit. Another object is to provide a screen atthe overflow opening together with paddle means for agitating the wasteliquid adjacent the screen so as to permit the free flow of overflowliquids therethrough. Another object is the provision of a valvecontrolled discharge outlet for the washed pulp and another object isthe provision of a, jacket through which a heating medium such as steamor hot water may be cir- I culated to heat the contents of the unit.Another object is the provision of means for-introdu.cing

steam or hot water into the interior of the tank whereby to cook thepulp. Another object is to perform the washing operation at atmosphericpressure.

With these and other objects and advantages in view, this inventionconsists in the sever-a1 novel features hereinafter fully set forth andmore particularly defined in the claim.

One embodiment of the invention is clearly illustrated in theaccompanying drawings in which:

Figure 1 is a vertical axial section taken through the apparatus;

Figure 2 is a horizontal section taken on the line 22 of Figure 1, and

Figure 3 is a detail cross section taken on the I line 33 of Figure l.

The type of stock ordinarily operated uponby the present washer isde-inked wastepaper stock which has been disintegrated, chemicallytreated and cooked, producing a cleansed pulp, all foreign materialsgoing into solution ready to be 1 Claim. (Cl. zit-49.6)

. washed out of the stock. Such foreign materials may consist of clay,water-proofing, starch,.glue, paraffin, grease, inks of all kinds, andother forelgn substances. Colored paper should have all of the colorremoved therefrom. All of these foreign materials must be washed out ofthe stock. The washer forming the subject matter of this specificationis constructed and equipped so that it will wash all foreign materialsfrom the pulp. This is done by putting a batch of treated. cooked stockin the washing unit. Fresh wash water is let in at the bottom of theunit, rises therein and causes the waste liquid to overflow through ascreen at the top of the unit whichis kept free of the pulp by suitablepaddle mechanism. The level of the stock in the unit is controlled by,the flow of fresh wash water. The fibers are retained in the unit by awire mesh screen based according to the requirements. The

stock is agitated in the unit to keep it in oil'- culation as thefresh'wash water rises from the bottom of the unit until it graduallyforces out the waste liquor from the material so that after sufficientwashing time the batch of stock is thoroughly cleansed of all foreignmatter.

Referring now to said drawings which are merely illustrative of oneembodiment of the invention, 10 designates a tank, preferablycylindrical, and having a concave bottom ll. ported in the tank abovethe bottom I l is a false bottom I! which is provided with amultiplicity of perforations l3, throughout its area or throughout onlya portion of its area. Soldered or otherwise secured to the upper faceof the false bottom I2 is a wire mesh screen H which covers theperforations and prevents the fibers from escaping therethrough.Supporting rods or posts 51 are secured to the tank bottom H and supportthe false bottom I2. I

Suitably spaced from the side wall and bottom wall of the tank is ajacket l5 for receiving a heating medium such as steam 'or hot water forsupplying heat to the interior of the tank. A steam or hot water inletpipe It opens to the space between the tank wall and jacket and anoutlet pipe I! leads away from this space. For supplying steam or hotWater to the interior of the tank, a valve controlled supply pipe I8 isprovided which opens. to the interior of the tank.

The entire unit may be supported by supporting means such as legs 20bolted or otherwise secured to the tank and connected by a ring-likemember 3 side wall and bottom wall of the tank may be held in spacedrelation by suitable stay bolts 19 or otherwise as is well understood bypersons skilled in the art to which this invention pertains.

The false bottom I2 is provided with a discharge opening 22 from which adischarge conduit 23 leads to the bottom wall ll of the tank. Thedischarge conduit 23 may be flanged at its ends and the flanges may bewelded to the false bottom and tank bottom or otherwise secured theretoas may be found desirable. A valve such as a slide valve 24 controls thepassageway through the discharge conduit. The discharge conduit is shownas provided with a valve housing 25 into which the valve 24 may be slidwhen opening the passageway through the discharge conduit and means areprovided for opening and closing said valve which means are shown ascomprising rack teeth 28 provided upon the under face of the valve andmeshing with pinions 21 carried by a shaft 28 journaled in suitablebearings and extending to the side of the. tank where it is providedwith a hand wheel 29 for its manipulation. The valve 24 slides in ways30 formed on the discharge conduit. Discharge openings are provided inthe tank bottom and jacket below the discharge conduit, and a threadednipple 23a may be welded to the jacket around the discharge opening, towhich a discharge pipe may be attached. A ring-like spacer 2312 may beinterposed between the tank bottom and jacket around the dischargeopenings and welded to the tank bottom and jacket.

The upper end of the tank is open so as to permit liquids to overflowits upper edge, and extending upward from said upper edge is a screen orstrainer 3| of suitable mesh which. holds back any pulp that mightotherwise overflow with the liquids. The screen may be conical orcylindrical and is secured to the tank in any desirable manner and it ishere shown as formed with a downwardly projecting flange 41 securedbetween the inner face of the tank and a ring-like member 42 riveted orotherwise secured to the tank wall. A reinforcement ring 311; is securedto the upper edge of the screen.

Rotatable paddle means 32 are provided for clearing the inner face ofthe screen of any pulp that might collect thereon and said paddle meansis shown as comprising a paddle-carrying ring 32a provided with radialspokes 33 that project from a hub 34 which is fixedly mounted upon anagitator shaft 35. Spaced around the ring-like member 32a is a pluralityof paddles 36 which nearly contact with the inner face of the screen andare secured to the ring as by brackets 31. Secured to thewall of thetank slightly below its upperend'is an annular gutter 38 into which theoverflow liquid from the tank falls and is conducted away by a dischargepipe 39. The gutter 38 may be provided with a downwardly extendingannular flange 40 riveted or otherwise secured to the wall of the tank.

The agitator shaft 35 extends vertically through the axis of the tankand its lower end is j ournaled in a thrust bearing 58 mounted upon abearing bracket 59 welded or otherwise secured to the bottom wall ll ofthe tank. The upper end of the agitator shaft is journaled in a bearing60 carried by the framework of the unit. This framework may convenientlycomprise oppositely disposed bracket plates 43 secured to'the side wallof the jacket l as by angle irons 44 bolted or otherwise rigidlyfastened thereto, upright posts 45 rigidly connected with the bracketplates 43 and channel bar members 46 rigidly secured to the upper endsof the posts. A platform 41 is secured to the upper sides of the channelbar members 46 and furnishes the support for the motor 48 and its speedreducing gearing 49 which is coupled to the agitator shaft 35.

Extending radially from the agitator shaft is an agitator whichcomprises agitator; arms 50 that terminate at places adjacent the innerface of the tank wall Ill. The agitator arms 50 are disposed one abovethe other along the length of the agitator shaft and the arms in eachplane are arranged equidistantly in groups and are secured to a hub 5!which is rigidly mounted upon the agitator-shaft.

Riveted or otherwise rigidly secured to the outer ends of the agitatorarms 50 are spirally arranged conveyer bars 52 that act to circulate thecontents in an upward direction as the bars are rotated through thetank. Intermediate the agitator arms 50 are shorter agitator arms 50awhich are rigidly secured to hubs 51a mounted on the agitator shaft. Theshorter agitating arms 50:: are disposed in vertical planes intermediatethe vertical planes of the longer agitating arms 50 as is clearly seenin Figure 2.

The bottom of the tank is formed with inlet openings 53, 54 from whichlead valve controlled liquid supply pipes 53a, 54a, and the bottom isalso formed with discharge openings 55, 56 from which lead valvecontrolled discharge pipes 55a,

In the operation of the pulp washer, a quantity of Wash water isadmitted through either or both ofthe supply pipes 531:, 54a, and risesthrough the perforations I3 in the false bottom and enters the mainchamber of the tank. A batch of the material to be operated is thencharged through the open top of the tank and allowed to stand for ashort while, after which the valve of one of the discharge pipes 55a, or56a is opened permitting the dirty water to drain out through theperforations in the false bottom and be discharged through the opendischarge pipe. By permitting the dirty water to drain out of the tankbefore the washing operation begins, there is quite a saving of powerand wear and tear on the mechanism, and hastens the washing operation.After the dirty water has been discharged, the valve of the opendischarge pipe is closed and the valve of one of the supply pipes 53a,54a is opened thereby admitting wash water to the main chamber of thetank which rises therein to the top thereof and overflows through thescreen 3! into the gutter 38. The motor is started and it rotates theagitator shaft and therewith the agitator arms and the spiral bars 52thereby agitating the mass, during which time wash water is beingcontinuously supplied thereto and rises through the mass carrying withit the foreign materials and overflowing through the screen 3| into thegutter 38. Simultaneously, the paddle means is rotated by the agitatorshaft and any pulp particles that may collect on the inner face of thescreen are dislodged therefrom, thus keeping the screen free andclearfor the passage of the waste liquid.

When the washing operation has been completed, the wash water supplypipe is shut off and one of the discharge pipes is opened, therebypermitting the liquid to drain out of the main chamber of the tank andduring the draining operation the agitator is kept in motion so that thelowermost agitator arms may stir the pulp lying pulp to be dischargedfrom the tank into suitable receptacles provided therefor.

If heat is required in the washing operation, steam or hot water isadmitted to the jacket i5 through the supply pipe l6 and if it isdesired to cook the pulp, steam may be admitted through supply pipe l8to the interior of thetank.

Furthermore, one of the supply pipes 53a 01' 54a may lead from a tankcontaining a bleaching solution and when it is desired to bleach thepulp, the valve of the pipe leading from said bleaching solution tank isopened thereby admitting bleaching-solution into the tank. When thebleaching operation has been completed, the valve of said supply pipe isclosed and the valve of one of the discharge pipes 55a, 56a isopened todrain off the bleaching solution and this pipe may lead to a tankintowhich the bleaching solution may be discharged for further use. Afterthe bleaching operation, the wash water pipe 53a or 54a is opened to thetank thereby admitting fresh clear water in an upward direction to thepulp whereby it may be thoroughly rinsed. The agitator may be kept inmotion during all of these operations if necessary.

Having thus described the present invention, it is obvious that variousimmaterial modifications may be made'without departing from the breadthand scope of the present invention. Therefore, no limitations should beplaced on the exact form, construction, arrangement and combination ofparts herein shown and described or to the uses mentioned excepting asshall be determined by the breadth and scope of the appended claim.

What I claim as new and desire to secure by Letters Patent is:

In a pulp washer and in combination, a tank open at its upper endandhaving a concave bottom, a liquid supply pipe opening through saidbottom, a perforated false bottom above the concave bottom, a screenupon said false bottom, a valve controlled discharge pipe opening fromsaid concave bottom, and a valve controlled pulp discharge outletopening from said false bottom and extending through the concave bottom,a conical screen secured to the wall at its top and extending up therei.m, rotatory paddle means having paddles dispor d adjacent the conicalscreen, means for rotating the paddle means, and a gutter disposed aboutthe tank wall below the conical screen into which waste liquid overflowsfrom the tank I JOHN NEUMANN.

REFERENCES Crrnp The following references are of record in the file ofthis patent: 1

UNITED STATES PATENT Number Name Date 1,425,497 Merrill Aug. 8, 19221,754,667 Cabrera Apr. 15, 1930 689,472 Edson Dec. 24, 1901 1,966,456Myers July 17, 1934 2,139,924 'Woodruff Dec. 13, 1938 1,000,086 Goetz etal. .1 "Aug. 8, 1911 1,439,706 Kneuper Dec. 26, 1922 773,222 Porter Oct.25, 1904 860,930 Merten July 23, 1907 654,647 Koppelmann July 31, 19002,021,616 Stuart 1 Nov. 19, 1935 1,982,002 Hatch Nov. 27, 1934 1,245,839Waring et a1. Nov, 6, 1917 1,817,973 Roza Aug. 11, 1931 FOREIGN PATENTSNumber Country Date 252,791 Germany Oct. 26, 1912 France Apr. 11, 1906

